Beta-2-Microglobulin, Urine B-Cell CD20 Expression Benztropine Quantitative, Serum or Plasma Beta-Catenin-1 by Immunohistochemistry Biotinidase Deficiency (BTD) Sequencing Blood Smear – with Interpretation Biotinidase, Serum (with Paired Normal Control) Bloom Syndrome (BLM) 1 Mutation Bismuth, Blood BK Virus, Quantitative PCR Beta-hCG, Urine Qualitative BK Virus, Quantitative PCR, Blood Beta-Hydroxybutyric Acid BK Virus, Quantitative PCR, Urine BF-1 by Immunohistochemistry Bladder Tumor Associated Antigen Bicarbonate (HCO(sub:3)), Urine Blastomyces Antibodies by CF and ID Bile Acids, Fractionated and Total by LC-MS/MS Blastomyces Antibody by CF